Mechanical pencil



April 4, 1950 B. ZELENITZ MECHANICAL PENCIL Filed May 29, 1946 u i E Q \m & QH Y x E g Patented Apr. 4, 1950 UN [TED STATES; OFFICE MEGHANICALIZENCILI Benjamin Zelenitz; nmoalymjml. ApplicationMayfiS, 1946 Serial.-No..673,1ll1

This. invention relates, to devices; such as. mechanical pencils.

One. object. of. the. invention is to; provide. a device. of the character; described having improved. means for the continuous automatic. feed of an element,.only asthesame is consumed.

The. element. referredv to includes. a plurality of rod-likev parts, which. converge to. an. operating. point'at. whichthey laterally, angularlv' abuteach other to-resist and. prevent. feeding. thereof except. as the. operating portion. is consumed, there. being. a means-for evenly: advancing: both rod-like parts by exerting. a constant pressure. thereon which. maybe. of yieldingnature or merely so-weak. as. to. be. ineifectiveto. overcome the. resistance at. the'operating, portion of the parts. Accordingly reclai 01. rad-er I thesnhj'ofried claims; and. illustrated in. the an;

the; point of lateral abutment travels alongthe.

weak ,..as stated; acne-way, clutch. may serve to.

resist. reverse movement. of the. rod-like. parts. Thelatter may consist. of. pencil leads, welding.

rods and-similar devices, but the advantages of.

theinventionare best. exemplifiedin amechanical pencil which is-believedto be afield of invention different from welding devices. and. the. like.

It. is therefore. an object of the invention. to

furnish. a device. such as. a mechanical. pencil:

having improved, self-feeding means, with as:

sociated means; to prevent reverse. movement. as. where the elements. 01:. leads. are. subjected to.

pressure in writing or in other operations- Another object. of? the invention is to. furnish.

a mechanicalipencilin whichrelativel'y long, element's or leads. are sprung. to. arcuate paths. to thus. increase the angle of convergence within the relatively. narrow. limits of a penciL.

Another object of the invention is, the. provision off. a mechanical. pencil having improvedmeans.

comprising relatively few, and; simpleparts. and.

whichis: inexpensive. to manufacture and; assemble,.' durable, reliable and; highly efficient; in. use; Other. objects: and advantagespf; the. invention. willibecoine'f apparent as the specification proceeds. I

With the aforesaid objects in view, the invention. comprises.- thenovel featnres,j eombinations and. arrangements. of pants hereinafter described.

in. their preferred. embodiments pointed. out in 'nexed; am mgwne em'nke parts: are designated by the samelreierence'characters. throughout the. several viewsl.

In- 'thedraavingi:- Figure 1. is; a. central longitudinal sectional view with. parts. removed. showing a. mechanical pencil.

emboldyin'gthe. invention.. i v Figs 2. is a view like that. of Fig. 1 but partly in elevationlandpartly in section along. acentral.

longitudinal plane, with parts removed. Fig.3. is.- a. view at. right anglesto the. toregoingiwith parts. in. elevation, parts in section,.

and" parts' removed, showingthe. pencil in course. I of fbe'ing: assembled with its coventhe. clutch. be?

ingininoperativeposition.

Fig. 4. is: an. enlarged. sectionalview of. the: leads separated; frbmeach. other at a. point. along. their. convergentipaths.

Fig. 5 is'a. similar. view. but. showing the. leads. inilateralengagement; with. each'other at a point.

of the common writingendfportion formed-by; the

leads.

Rig. 6." isan enlarged fragmentary sectional view,. with-parts. removed. showing the clutch iii operative position. I

Fig. '7'is a; sectional view on line. I -1' of.Fig. 6;

Fi 8shows. a modificationwith arcuate paths for thezleadsi 1 Fig; 9Jis. atransverse: section of the device of.

8' showing; the. modifiedrlead retaining means for thearcuatepaths.

the whole;

It. will be' obvious. to' those skilled in the art to which the-invention. appertains,. that the. same may be incorporated in several diflferent constructions" The accompanying drawing; there fore, issubmitted merely" as showinga preferredj' exemplification ofthe invention.

Referring in' detail to the drawing; l0 denotes a devicesu'ch' as; a. me'c hanical pencil. embodying: thefi invention; The-same...may include a. core memberfi having. taperedl point. portion H. from? whiclrfthereijextends. axially a core..,element I21. andilan annular. internally. andrexternally threaded sleeve l3extending about the adjacent portion; of the coreelement. The parts H, l2 and: 13 may. belldf one -pieces construction; A. cover. I41; is adapted-to 1 axially receive the.- com element H- andfise iiernovablyconnectedztoi-thersleeve |-8 r at its 18 maintained by the guide meansiin confronting relation to each other as shown in Fig. 4, these faces coming into contact with each other ad 1 1 jacent to the writing point l1 as shown in Fig. 5.

Illustratively, the guide means include-the-gen-- erally cylindrical core element l2 having -open-.

ings is formed therein along a diametrical plane.

These openings in the core element 12 constitute longitudinal slots open at the periphery thereof. The slots disappeanat the curved free end portion of the core element. Adjacent to the opposite end of the latter, they lead at 2i into the bores" or holes 22 which are alined with the slots and extend through the point portion I I. 'The slots l9 and the openings 22 afford straight, continuous, convergent paths for the leads I 6. Such paths are providedby the base portions of the slots 19, these base portions providing flat or plane seats 23 conforming to the flat faces Id of the leads l6, and the bores 22 may be-correspondingly shaped if desired for example to the halfround configuration. I

A feeding means may include a common element 2 for the leads movable along a diametrical slot opening 25 of the core element 12. This slot 25 intrcommunicates the lead guide slots :9 but is substantially narrower than the latter; thus the seats 23 are split, but they have sufficient bearing area for the leads 16. The element 24 may be connected to or form a part of a Single tension coil spring 26 taking around the core element 12 which forms a guide therefor, this spring being removably threaded into the inner thread of the sleeve 13. Thus there is a common structure applying the same pressure on both leads 16, with the element 24 bearing on the inner ends thereof, the parts cooperating to tend to keep the leads seated on the seats 23.

--The spring 25 represents any feeding means which is of yielding character or so weak that it cannot overcome the obstruction afforded by the,

lateralabutment of the convergentleads at the common writing point 11 but being capable of continuously automatically advancing the leads as the writing point wears down, and when the writing pressure on the leads is momentarily relieved. Of course, the spring tension becomes weaker as the feed of the leads progresses. For these reasons, and to strongly resist the writing pressure on the leads, a one-way clutch is provided adapted to readily travel with the spring but resisting reverse movement of the leads. For a uniform balanced effect, the feeding means includes a plurality of clutch elements or detent means 21. Each may be formed likea U-shaped or spring clip having a loop 28 clipped around a coil of the spring 26 from which loop extend the legs 29, 30. The legs 30 are adapted to ride along the cover 14, while the legs 29 are received in longitudinal slots 31 of the core element 12, these' legs 29 being preferably inwardly bowed to afford at '32 the curved end 2| of the core element? 4 whereby the clutches 21 may be moved 'to the inoperative positions shown in Fig. 3. When the cover I4 is removed, the clutches 21 expand and hence would obstruct replacement of the cover. To avoid such obstruction, the operator moves the clutches to the position of Fig. 3, the curved slots or openings 32 affording clearance for the legs 29 to permit the clutches to be swung toward each other about the spring mounting, coil as a pivot. As the lead feeds forward to writing position, the spring 26 advances the clutches 21 which thereupon swing outwardly away from I each other to the position shown in Fig. 6, with the legs 29, 30 becoming deflected toward each other to a compressed operative position conjointly maintained by the core element and the cover. The slots 31, 32 afiord continuous guiding engagement for the clutches. And in the operative position thereof, the clutches will not interfere with removal of the cover nor will the clutches be shifted by rotary' or longitudinal movement of the cover in course of its removal. I In use, the pencil is loadedby removing the cover 14 and unscrewing the spring 25 from the sleeve l3, thus removing with it the feeding element 24 and the clutches 21. Then the leads IE are placed in the guide slots 19 and moved into the guide holes 22. Now the spring is applied and engaged with the sleeve 13, while stretched so that the element 24 clears the core I2. The element is now inserted in the slot 25 and the spring" ing each other and abut at the writing end 11 to obstruct outward movement under the spring pressure except as the end 11 wears down, causing progressive shifting of the abutting portions along the leads. Writing pressure is resisted'by the: clutches 21. A common, compact writing point is afforded which is always uniform since the leads are evenly fed, and writing pressure will not I cause the abutment relation to break the leads because such pressure tends rather to the abutment pressure.

In Figs. 8 and 9 is shown a modified pencil 35 diminish diiiering principally in that the leads 36 are,

width equal to that of the slot 25 to affordsnu r,

fitting guides for the bowed. or sprung leads .jtoj

thus avoid further springing and breakage there-.1

of under longitudinal pressure; The feed .ele-' ment is thus guided by the openings 40 as well as by the slot 25. The core as may e be used with;

advantage in the pencil I0.

Iclaim: 'f I l. A mechanical pencil having means for gui ing' a plurality of leads along lines so convergeht that the le-ads' laterallyabut each other at'theii" outer ends to form a writing point, and spring means for feeding said leads as the abutting ends become worn out in writing.

2. A mechanical pencil having means for continuously automatically and simultaneously guiding and feeding a plurality of leads, including means to cause the outer end portions of the leads to converge substantially to a, point and thus to obstruct and arrest their feed except as the end portions become worn out in writing to permit the leads to feed until they again obstruct each other and arrest the feed.

3. A mechanical pencil having means for guiding a plurality of leads along convergent paths so that the writing end portions of the leads meet substantially at a common writing point, and means for yieldingly continuously urging advance of the leads as the end portions become worn but being otherwise insufficient in strength to advance the leads.

4. A mechanical pencil having guide means having convergent paths for a plurality of leads such that the leads meet at a common writing point and abut each other to thus arrest the feed of the leads, means for continuously yieldingly urging the leads to advance under equal pressure as the point becomes worn but being otherwise incapable of advancing the leads, and means for resisting reverse movement of the leads under writing pressure.

5. A mechanical pencil having means for guiding a plurality of leads along convergent paths such that the leads meet to form a common writing point, said leads being approximately halfround in cross section, the guiding means having means for maintaining the leads in such relation to each other that their flat surfaces meet at said writing point.

6. A mechanical pencil including means for holding a plurality of generally half round leads so that their flat faces confront each other, including means for guiding said leads along convergent paths so that the leads laterally abut each other at their fiat faces to form a common writing point, and feeding means for advancing the leads as the common writing point wears down, the feeding means being so relatively weak and the said abutment being sufficient to resist the feedin means except as the common writing point Wears down.

'7. A mechanical pencil including guide means for a plurality of generally half round leads along convergent paths and having seats to cause the flat faces of the leads to confront each other, with the leads meeting at a common writing point at which they abut each other at their flat faces, and means for feeding the leads to equally advance the same.

8. A mechanical pencil including guide means providing convergent paths for a plurality of leads so that the latter meet and laterally abut each other at a common writing point, the guide means having a plane seat for the flat faces of the leads to maintain the faces in confronting relation to each other, and feeding means constantly urging the leads to advance, the angle of convergence adjacent to the writing point being sufficient to prevent the leads from advancing except as the writing point becomes worn down so that the area of abutment is transferred to next adjacent portions of the leads upon advance thereof by the feeding means.

9. A mechanical pencil according to claim 5, wherein the feeding means include a common spring for advancing the leads.

10. A mechanical pencil according to claim 5 wherein the guide means includes a core having longitudinal convergent guide openings for the leads and longitudinal passages communicating with said openings, the feeding means having a common spring for the leads coaxial with the core and having portions in said passages and openings to feed the leads at different points along their convergent path.

11. A mechanical pencil according to claim 5 wherein the feeding means includes a yieldable feeding element and detent means inoperative upon advancing movement of the leads but resisting reverse movement thereof under writing pressure on the leads.

12. A mechanical pencil according to claim 5 wherein the convergent paths include arcuate sections to vary the convergence and increase the same toward the writing point.

13. A mechanical pencil having guide means defining arcuately convergent paths for a plurality of leads, and means for feedin the leads simultaneously along said paths.

14. A mechanical pencil comprising means for yieldably feeding a lead including an elongated core member, a tension coil spring positioned about said core member for supplying the feeding force, an elongated cover fitted to include said core and spring, and a one-Way detent means pivoted on a coil of said spring engaging said core and cover for resisting reverse movement of the lead.

15. A mechanical pencil comprising means for yieldably feeding a lead including an elongated core member, a tension coil spring positioned about said core member for supplying the feeding force, an elongated cover fitted to include said core and spring, and a one-way detent means pivoted on a coil of said spring engaging said core and cover for resisting reverse movement of the lead, said detent means and core being so constructed and arranged as to permit the detent means to pivot out of the way of the cover to facilitat mounting the latter and to return to operative position between the core and cover upon advance of the detent means in course of feeding the lead.

16, The mechanical pencil defined in claim 14 including divergent lead guiding passages in the core whereby the leads abut each other laterally to form a common writing point and thus resist feeding of the leads by said feeding means.

BENJAMIN ZELENITZ.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 220,982 McCarty Oct. 28, 1879 2,083,309 Applegate June 8, 1937 

